That single word belies the deep panic and fear behind the reason for the poster it’s on. Someone’s gone, not where he should be, and his family believes something’s wrong. They’re terrified because at some time in the ensuing days, as the poster falls to the elements and as you’ll read in “An Unexplained Death” by Mikita Brottman, missing can become mystery.

In the early evening of May 16, 2006, Rey Rivera left his Baltimore home in a hurry, taking his wife’s car. He’d received what’s presumed to be a work-related phone call minutes before he left, but investigators still don’t know who called him.

No one was ever able to ask because, days later, Rivera was found dead in Baltimore’s Belvedere Hotel. He’d fallen through the roof into an abandoned office that had been a swimming pool in the Belvedere’s early years, but was now covered-over. The medical examiner said he hit the floor of the empty office, feet-first.

Mikita Brottman lived on the fifth floor of the grand old hotel-cum-condominium, and she was immediately captivated by Rivera’s passing. She admits that she’s always been fascinated in the “dark side,” in an X-Files sort of way, and death is of particular interest because of its unknowability. She admits that she’s tried all her life to experience the paranormal. She began digging deeper into what had become a mystery.

Rivera was a tall athletic man, an immediately likeable kind of guy. He had a bit of a temper as a youth and was said to be impulsive with money, but his life seemed to be going well. Friends refused to believe that he killed himself.

Though she’d never met Rivera, Brottman believed likewise but the more she learned, the odder the evidence. Rivera had just left a job that made him unhappy, for reasons that Brottman suggests were “tangled.” Details were forgotten, various players refused to speak with her, and documents were “lost.” And person after person after person warned Brottman to “be careful”…

“An Unexplained Death” is the kind of book that’s perfect for the person who poked at road-kill as a child. It’s for the former kid who half-bravely half-thought about stumbling across a body in the woods someday, or who happily slept in a cemetery on Halloween. It’s creepy, and it’s very, very good.

In her story, and that of Rey Rivera, author Mikita Brottman makes readers squirm. Not only do we learn a lot of shivery things about missing persons, but she also tells more about suicides, autopsies, and dead bodies than most true crime books would ever dare tell. Put it in a century-old hotel that’s seen its share of unsettling suicides, and you have a book that will make you cringe, check the locks, and read some more.

Beware that this is not for anyone prone to nightmares. True crime fans may not like the personal injected into the process. But if you love a mystery that’ll leave you unnerved and twisting, “An Unexplained Death” should not be missed.